Fiber optic connectors of a wide variety of designs have been employed to terminate optical fiber cables and to facilitate connection of the cables to other cables or other optical fiber transmission devices. A typical fiber optic connector assembly includes a ferrule which mounts and centers an optical fiber or positions multiple fibers within the connector. The ferrule may be fabricated of such materials as ceramic or plastic. A ferrule holder of the connector embraces the ferrule and may be fabricated of such material as molded plastic. If the ferrule holder is not part of the connector housing, an outer housing may be provided about the ferrule holder for mating with a complementary connector or other mating connecting device.
A pair of fiber optic connectors or a connector and another optical fiber transmission device may be mated in an adapter which aligns the fibers to provide low insertion losses. The adapter couples the connectors together so that their housed fibers connect end-to-end. The adapter may be an in-line component, or the adapter can be designed for mounting in an opening in a panel, backplane, circuit board or the like.
Fiber optic connectors often are assembled at a factory where bare fiber ends of a fiber optic connector are terminated in the ferrule of the connector assembly. The fiber ends typically are permanently epoxied within passages in the ferrule. The end faces of the fiber ends are highly polished flush with the mating face of the ferrule. However, in many applications, it is desirable to terminate the fiber ends in the field where the elaborate termination and assembly equipment, fixtures and the like typically used in a factory are not available. In field termination, “fiber stubs” have been used to facilitate termination. In other words, a subassembly comprising a ferrule and some sort of fiber alignment component is terminated to one or more short pieces (“stubs”) of optical fibers at the factory. The fiber stubs are adhered within the ferrule and the end faces thereof are polished flush with the mating face of the ferrule, as is done with conventional or completed fiber optic connectors. This subassembly then is used in the field to terminate optical fibers to the factory terminated fiber stubs. The present invention is directed to improvements in such field termination systems and connectors.